/Engine/Source/Editor/Kismet/Public/BlueprintEditorModule.h
Register a customization for for Blueprint functions
virtual [FDelegateHandle](API\Runtime\Core\Delegates\FDelegateHandle) RegisterFunctionCustomization ( [TSubclassOf](API\Runtime\CoreUObject\Templates\TSubclassOf)< [UK2Node_EditablePinBase](API\Editor\BlueprintGraph\UK2Node_EditablePinBase) > InFieldClass, FOnGetFunctionCustomizationInstance InOnGetFunctionCustomization )